scholarly journals Tamaño óptimo de parcela e incidencia de la podredumbre blanca del capítulo del girasol en el sudeste bonaerense

2019 ◽  
Vol 118 (1) ◽  
pp. 44-51
Author(s):  
M. Anabella Dinon ◽  
Santiago Delgado ◽  
Fernando Castaño
Keyword(s):  
Helianthus Annuus ◽  
Sclerotinia Sclerotiorum ◽  
Helianthus Annuus L

Para conocer el tamaño de parcela que permita medir con eficiencia la incidencia de la Podredumbre blanca del capítulo-PBC de girasol (Helianthus annuus L.) se evaluó, en Balcarce, un par de híbridos en ensayos de uniformidad durante 2016 y 2017. Todos los capítulos de cada ensayo se inocularon con Sclerotinia sclerotiorum (Lib.) de Bary. Durante el primer año y para cada híbrido, se delinearon 165 parcelas mínimas, de un surco de 2m x 0,70m (=1,4m2). Mientras que en el segundo, la cantidad fue de 150. En cada una de esas parcelas básicas se registró la incidencia de PBC. Luego se generaron ocho tamaños más, combinando las parcelas mínimas adyacentes en distintos arreglos. El tamaño óptimo se señaló detectando el punto de máxima curvatura en gráficos que relacionaron el coeficiente de variación y los nueve tamaños de parcelas considerados. El análisis de varianza combinado sólo detectó efectos significativos de híbridos (H), años (A) y HxA sobre la incidencia de PBC. Los resultados obtenidos no permitieron señalar un único tamaño de parcela, dado que el óptimo dependió del nivel de resistencia del híbrido y del año de experimento. Así durante 2017, año más favorable a la enfermedad, el tamaño óptimo de parcela para los dos híbridos, resultó inferior que el señalado en 2016. Bajo las condiciones en que se desarrolló el experimento, el uso de parcelas de mayor superficie al señalado, no provocaría un incremento significativo en la fiabilidad de medición de la INC, por unidad de recursos utilizados.

Importance of Coniothyrium minitans in survival of sclerotia of Sclerotinia sclerotiorum in wilted sunflower

1977 ◽  
Vol 55 (3) ◽  
pp. 289-295 ◽  
Author(s):  
H. C. Huang
Keyword(s):  
Helianthus Annuus ◽  
Sclerotinia Sclerotiorum ◽  
Growing Season ◽  
Root Surface ◽  
Causal Agent ◽  
Stem Rot ◽  
Coniothyrium Minitans ◽  
Basal Stem Rot ◽  
Helianthus Annuus L ◽  
The Relationship

The relationship between Sclerotinia sclerotiorum, causal agent of wilt or basal stem rot of sunflower (Helianthus annuus L.), and its hyperparasite Coniothyrium minitans was investigated in a sunflower field naturally infested with the two organisms. Sclerotia of S. sclerotiorum were collected biweekly from roots and basal stems of wilted plants and analyzed for infection by the hyperparasite. The results showed that C. minitans parasitized and killed the sclerotia produced on the root surface. This hyperparasite continued to parasitize the pathogen inside the root and upwards into the base of the stem, thus infecting the sclerotia produced at these sites. By the end of the growing season, 59%, 76%, and 29% of sclerotia on the root surface, inside the root, and inside the stem, respectively, had been killed by the hyperparasite, while 4%, 9%, and 68% of the sclerotia at these locations were healthy. Death of the rest of the sclerotia was due to organisms other than C. minitans. The data also indicate that C. minitans is more effective in parasitizing sclerotia produced on or inside the root than those produced in the basal stem.

scholarly journals The Infection Processes of Sclerotinia sclerotiorum in Basal Stem Tissue of a Susceptible Genotype of Helianthus annuus L.

2012 ◽  
Vol 40 (1) ◽  
pp. 143 ◽  
Author(s):  
Robab DAVAR ◽  
Reza DARVISHZADEH ◽  
Ahmad MAJD ◽  
Ardashir KHARABIAN MASOULEH ◽  
Yobert GHOSTA
Keyword(s):  
Helianthus Annuus ◽  
Sclerotinia Sclerotiorum ◽  
Host Cells ◽  
Post Inoculation ◽  
Plant Surface ◽  
Susceptible Genotype ◽  
Helianthus Annuus L ◽  
Fungal Hyphae ◽  
Infection Processes ◽  
Host Tissues

Sunflower, Helianthus annuus L., is a major oil seed crop widely cultivated throughout the globe. White mold, caused by necrotrophic pathogen Sclerotinia sclerotiorum (Lib.) de Bary, is a common and widespread pathogen of sunflower. The infection process of S. sclerotiorum was studied in the stem base of infected host tissues by light microscopy and Hemi-thin sectioning techniques. Host-pathogen interactions were examined at the plant surface and cellular level of a susceptible genotype (C146), 12, 24 and 48 h of post inoculation. The results showed that the appressoria were formed and the hyphal strands branched upon contact of pathogen with the host surface. Moreover a direct penetration of fungal hyphae was observed through the cuticle within 12h of inoculation. Microscopic observation of inoculated tissues after 24 hours revealed that fungal hyphae have developed both inter- and intra-cellular layer. Moreover, the fungal hyphae growth was incremental among and inside the host cells. The host cells were completely colonized by fungal mycelium 48 hour after inoculation, leading to a tissue collapse. The hyphae invaded the dead host tissues and emerged from the host tissue after extensive colonization. The present study has detailed the infection processes and pathogen development both at plant surface and inside the host tissues. The results of this study will be useful for engineering of disease-resistant genotypes and development of markers for screening pathogen resistance individuals.

scholarly journals Cobertura nitrogenada em girassol sob plantio direto na palha: teores de nutrientes nas folhas

2004 ◽  
Vol 2 (1) ◽  
pp. 65 ◽  
Author(s):  
Denise Bruginski De Carvalho ◽  
Amir Pissaia
Keyword(s):  
Helianthus Annuus ◽  
Sclerotinia Sclerotiorum ◽  
Helianthus Annuus L

O presente trabalho teve como objetivo avaliar o efeito de doses de N (nitrogênio), aplicadas em cobertura sobre o teor de nutrientes nas folhas de girassol (Helianthus annuus L.), em sistema de plantio direto. O experimento foi realizado na Fazenda Agripastos, em Palmeira, Estado do Paraná, em Latossolo Vermelho-Amarelo, cultivado em sistema de plantio direto desde 1976. Foram avaliadas as doses 0 (testemunha), 25, 50, 75, 100 e 125 kg de N ha-1 (uréia), aplicadas em cobertura no estádio V8. Os teores foliares de N, P, K, Ca, Mg, Fe, Mn, Cu e Zn foram determinados no estádio R4. Foram avaliados: número de plantas acamadas, quebradas e com sintomas de podridão do capítulo (Sclerotinia sclerotiorum). A relação entre os teores de N nas folhas (y) e as doses de N aplicadas (x) foi linear (y = 44,4 + 0,07 x, R2 = 0,87). Não foram evidenciados sintomas de excesso, mesmo nas maiores doses de N. O N aplicado em cobertura alterou o seu teor nas folhas, mas não alterou os teores de P, K, Ca, Mg, Fe, Mn, Cu e Zn.

The inheritance and biochemistry of resistance to Sclerotinia sclerotiorum leaf infections in sunflower (Helianthus annuus L.)

Euphytica ◽  
1991 ◽  
Vol 58 (3) ◽  
pp. 209-219 ◽  
Author(s):  
F. Casta�o ◽  
M. C. H�mery-Tardin ◽  
D. Tourvieille de Labrouhe ◽  
F. Vear
Keyword(s):  
Helianthus Annuus ◽  
Sclerotinia Sclerotiorum ◽  
Helianthus Annuus L

THE PROBLEM OF SAFE SUNFLOWER (Helianthus annuus L.) USE FOR FOOD AND FODDER PURPOSES (review)

2018 ◽  
Vol 53 (3) ◽  
pp. 485-498
Author(s):  
G.P. Kononenko ◽  
◽  
M.I. Ustyuzhanina ◽  
A.A. Burkin ◽  
◽  
...  
Keyword(s):  
Helianthus Annuus ◽  
Helianthus Annuus L

Sunflowers (Helianthus annuus L.) on Top of a Constructed Wetland as an Engineered Ecosystem to Clean Sewage Onsite

2014 ◽  
Vol 2014 (2) ◽  
pp. 83-91
Author(s):  
Alfredo Garcia-Perez ◽  
◽  
Mark Harrison ◽  
Bill Grant ◽  
◽  
...  
Keyword(s):  
Helianthus Annuus ◽  
Constructed Wetland ◽  
Helianthus Annuus L
Sign in / Sign up

Export Citation Format

Share Document